Controlling fertility in America is an economic issue

It doesn’t really matter who she is or how much money she makes. The likelihood that a single woman has had sex in the last year is roughly the same across income groups — about 70%.

What Happens Before And After Sex Varies Widely

However, what happens during and after having sex is very different depending on how much money a woman makes, though.

Birth rates, vary widely based on income. Single women between 15 and 44 from the lowest income bracket (>100% of the federal poverty line, $US11,770) in the US are five times more likely to have a child than women in the highest 20% of incomes (>400% of the poverty line).

A new Brookings paper takes a look at why that is.

The paper, by Richard Reeves and Joanna Venator, finds that both contraceptive use and abortion rates factor into the difference in the birth rate. Higher income women are more likely to use contraception, the contraception they use is more likely to be effective, and they are more likely to get an abortion than lower income women.

The Findings

In the study, Reeves and Venator controlled for both of these factors — contraceptive use and abortion — and looked at how it would affect the birth rate. They asked, if every income group used contraception and got abortions at the same rate as the highest income women, what would happen? Here are the results:

Pretty much across the board (with the exception of the fourth group, which is incomes 300-400% of the official poverty level and behaves strangely*), abortions at the rate of wealthy women cause the birth rate to go down by about a third. Using contraception at the rate of the wealthiest women causes the birth rate to go down by nearly half.

Here’s The Thing, Though

There’s a major caveat here, which is this isn’t a moral argument. A high birth rate for low income women is only bad if those women would rather not have had those children.

There’s a body of sociological research, most prominently being done by Kathryn Edin, that argues this isn’t true. Edin’s 2005 book with Maria Kefalas, “Promises I Can Keep,” finds that “child rearing was so central to young women’s outlook on life that they were unwilling to postpone having children until they could find a suitable husband — which could take years, if ever.”

However, it’s interesting to note that the Brookings paper actually surveyed the women in the study about how they would feel about getting pregnant and the results were largely equal across income groups:

Because of this, the paper’s authors think that income is the real factor that matters here. “Our view is that income gaps in accessibility and knowledge are the key factors here,” they write. This is an economic issue, and a policy issue.

The most effective forms of contraception — long-acting reversible types like IUDs — have high up-front costs, even if they are cheaper than other forms of birth control over the long run. Abortions are expensive, and depending on where you live, just plain unavailable without travelling a long distance. The ACA contraceptive mandate is to some extent helping with the former issue, but the government is more likely to restrict abortions than make them more available and affordable.

The fact is that controlling fertility remains expensive for women in this country.

* The group between 300-400% of the federal poverty level (that’s an income of roughly $US35,000-47,000 per year) behaves differently than other groups. I don’t have any idea why, but I wonder if there’s a stronger religious component here? Or if women at this level of income feel stable, but aren’t doing the career-ladder climbing that women at the top level are, so are more likely to decide to go ahead with an unintended pregnancy? Anyway, there’s no evidence for either of those theories, so moving on…

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